PACMAN is a novel hardware attack discovered by researchers at MIT CSAIL. PACMAN is what you get when you mix a hardware mitigation for software attacks with microarchitectural side channels. The researchers demonstrated that they can bypass Pointer Authentication (PAC) on the Apple M1 CPU.
Should you be worried? No. PACMAN is an exploitation technique- on its own it cannot compromise your system. While the hardware mechanisms used by PACMAN cannot be patched with software features, memory corruption bugs can. 
